/Engine/Source/Runtime/AudioCaptureCore/Public/AudioCaptureDeviceInterface.h
PCM audio format (bits per sample) supported by device layers (WASAPI, CoreAudio, etc.)
namespace Audio { enum EPCMAudioEncoding { UNKNOWN, PCM_8, PCM_16, PCM_24, PCM_24_IN_32, PCM_32, FLOATING_POINT_32, FLOATING_POINT_64, } }